Android Looper confusion

Question

Android is complaining that the code below needs to call Looper.prepare. I have tried adding Looper.prepare but the code crashes after the sixth execution, leading me to believe that it wasn't as simple as I thought. Any suggestion would be appreciated. Incidentally I wrapped this code in AsyncTask cause I needed a progress spinner while the query was being executed. If there is something simpler, please let me know.

private class doSearch extends AsyncTask<String, String, Cursor> {

    @Override
    protected Cursor doInBackground(String... searchstring) {

        [...]           
        CursorLoader loader = new CursorLoader(SearchActivity.this, codes, projection, mWhere, null, null);
        Cursor cursor = loader.loadInBackground();

        return cursor;
}

Maybe this answer can help you although it doesn't have AsyncTask: http://stackoverflow.com/questions/6732529/cant-create-handler-looper-prepare-in-inherited-activity/6732757#6732757 — Onuray Sahin, Jul 21 '11 at 15:21

score 0 · Answer 1 · answered Jul 21 '11 at 15:22

0

It usually means you are doing something UI related or calling a handler's sendMessage function from another (background) Thread than the main thread

answered Jul 21 '11 at 15:22

Vincent Mimoun-Prat

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Thanks, I get that. Do you have a suggestion for fixing it? – Michael Little Jul 21 '11 at 15:35

score 0 · Answer 2 · answered Jul 21 '11 at 16:13

You are Already in an AsyncTask. Async Task Loader is going to create another AsyncTask that is rooted within your threadpool. AsyncTasks have to be constructed on the UI thread. They will use this to grab the Looper needed. If you are going to write an async task yourself and want to bite off this cursor load in serial then use a non async cursor retrieving way. Or get rid of your AsyncTask and extend CursorLoader and override the deliverResult(Cursor) method to act as your callback. This would be similar to onPostExecute within AsyncTask

Android Looper confusion

2 Answers2